[OMPI users] Issue with MPI_Get_processor_name() in Cygwin

[Martín Morales via users]

Hello,

I have what it could be a memory corruption with MPI_Get_processor_name() in 
Cygwin.
I’m using OMPI 4.1.0; I tried also in Linux (same OMPI version) but there isn’t 
an issue there.
Below the example of a trivial spawn operation. It has 2 scripts: spawned and 
spawner.

In the spawned script, if I move the MPI_Get_processor_name() line below 
MPI_Comm_size() I lose the values of rank and size.
In fact, I declared some other variables in the  int hostName_len, rank, size; 
line and I lost them too.

Regards,

Martín

---

Spawned:

#include "mpi.h"
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char ** argv){
    int hostName_len,rank, size;
    MPI_Comm parentcomm;
    char hostName[200];

    MPI_Init( NULL, NULL );
    MPI_Comm_get_parent( &parentcomm );
    MPI_Get_processor_name(hostName, &hostName_len);
   MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Comm_size(MPI_COMM_WORLD, &size);

    if (parentcomm != MPI_COMM_NULL) {
      printf("I'm the spawned h: %s  r/s: %i/%i\n", hostName, rank, size);
    }

    MPI_Finalize();
    return 0;
}

Spawner:

#include "mpi.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char ** argv){
    int processesToRun;
    MPI_Comm intercomm;

      if(argc < 2 ){
        printf("Processes number needed!\n");
        return 0;
      }
      processesToRun = atoi(argv[1]);
      MPI_Init( NULL, NULL );
      printf("Spawning from parent:...\n");
      MPI_Comm_spawn( "./spawned", MPI_ARGV_NULL, processesToRun, 
MPI_INFO_NULL, 0, MPI_COMM_SELF, &intercomm, MPI_ERRCODES_IGNORE);

    MPI_Finalize();
    return 0;
}